author={Carl O. Lampland},
  journal={Publications of the Astronomical Society of the Pacific},
  pages={79 - 79}
  • C. O. Lampland
  • Published 1 April 1921
  • Physics
  • Publications of the Astronomical Society of the Pacific
Variations or fluctuations in brightness and changes in form (and possibly changes of position) of the structure in nebulae have so far been observed with certainty in only three objects, N. G. C. 1555 (Hind's variable nebula in Taurus), N. G. C. 2261 (Hubble's variable nebula in Monoceros) and N. G. C. 6729 (Schmidt's and limes' variable nebula in Corona Australis). In all these objects the fanor comet-shaped nebulosity is associated with prominent variable stars situated at the apex: T Tauri… 
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The Crab Nebula: An Astrophysical Chimera
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The Crab Nebula: A Gamma-Ray Factory in Our Backyard
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